Cards marked with numbers 13, 14, 15, …, 60 are placed in a box and mixed thoroughly. One card is drawn at random from the box. Find the probability that the number on the card drawn is
(a) Divisible by 5 (b) a number which is a perfect square
Total no of numbers = 60 – 13 + 1 = 48
[As total no's from a to b are (b – a + 1)]
(a) No Divisible by 5 in the given sequence = {15, 20, 25, 30, 35, 40, 45, 50, 55, 60}
So, we have
No of favourable outcomes = 10
No of total outcomes = 48
And,
Probability of an event
Therefore,
P(Getting a card having no divisible by 5)
(b) Perfect squares in the given sequence = {16, 25, 36, 49}
So, we have
No of favourable outcomes = 4
No of total outcomes = 48
And,
Probability of an event
Therefore,
P(Getting a card having a perfect square)